A hybrid fiber coaxial (HFC) network technology is an economical and practical integrated digital service broadband network access technology. An HFC network structure generally includes a network management system, a coaxial cable modem termination system (CMTS), an optical station, a cable modem (CM), a user side device, a fiber, a coaxial cable, an amplifier, an attenuator, and the like. However, a problem may occur in each device, each component, and each cable that are included in an HFC network. Therefore, an uplink signal of the HFC network is affected by various line distortions, such as a group delay and micro-reflection. To compensate for the line distortions in the HFC, the third-generation data over cable service interface specification (DOCSIS 3.0) defines a pre-equalizer. There is a pre-equalizer inside each CM, so that a signal can be reversely compensated before the CM transmits the signal. A fault group (that is, formed by at least one fault point) in the network may be found in advance by analyzing a pre-equalization coefficient of the CM, and an approximate location of the fault group is determined. However, in the foregoing fault locating method, only a relative distance between every two fault points included in the fault group can be calculated by using the pre-equalization coefficient of the CM, and each fault point cannot be located. In addition, a fault group including only a single fault point cannot be located.